After a long flight, I took my place in a slow moving but orderly queue waiting to pass through Indian immigration at Chennai airport. A middle-aged man with an attache case strode calmly past our ranks to insert himself at the front, blithely oblivious to the objections of those prepared to follow the rules. Darting across the yellow line that is supposed to keep the public at bay, he placed his passport on the immigration officer's desk, then stepped back and waited. Inside the passport there appeared to be a wad of folded notes. After a moment, the officer called him forward to the desk, stamped his now slimmer-looking passport, and let him into the country.

A cultural thing, you might think. Or a reminder that despite impressive growth rates and investment opportunities, India remains saddled with a corrupt bureaucracy. At the least, a mark of the gulf that still separates British and Indian societies.

But think again. On my way back from India, I found myself upgraded to club class (the economy section was overbooked). There was the flat bed, the champagne, the menu designed by celebrity chefs. And a perk I hadn't expected. As we approached Heathrow, those of us in club and first class who were not EU nationals were given a glossy voucher promising "a simpler, smoother journey through immigration control."

All I had to do was present the voucher to an official to gain access to the arrivals fast track, and hey presto, I'd be standing before an immigration officer, while my fellow passengers languished in the general queue.

For non-EU nationals, this can be snail-like, since arrivals from Africa and Asia are often quizzed at length. As someone who has spent many an hour waiting for admission to this country, I found the offer to "speed through immigration control" (illustrated with a blurry snapshot of a helmeted bobsleigh team) mighty tempting. But while I am happy to take advantage of flat beds and free booze, I draw the line at privileged access to a state official. As an upgraded passenger, I hadn't personally paid for it, but it still seemed a fast track too far. I decided to take my chances with the hoi polloi.

Most air travellers know that a business or first-class ticket buys a fast track through check-in and security (the former, understandable; the latter, questionable), but I wonder how many are aware that it can also buy near instant access to an immigration official?

The Home Office explains that BA covers the cost of the extra member of staff, that there is no burden on the taxpayer and no diminution of existing services to the public. They also insist that once in front of an immigration officer, everyone is treated exactly the same.

But a quicker service is a significantly better service. And will an Indian or Pakistani passport holder presenting himself to immigration officers as part of an exclusive business- and first-class queue really be treated the same as his counterpart in the undifferentiated melee outside? What's more, by extending the apartheid of the airport lounge into the domain of the state, the arrivals fast track sets a worrying precedent. Will corporations soon be able to buy vouchers for fast-track access to police or courts?

Whatever the dilemmas surrounding queue-jumping when it comes to health or education, they're multiplied many times over when the queue being jumped is an immigration one. Here personal wealth is used not to opt out of state provision but to purchase special access to it.

The advantage of the Heathrow scheme for BA, locked in fierce competition for the lucrative high end of the market (frequent and corporate flyers), is obvious. But why should the state get involved? Where's the advantage to the taxpayer, even discounting quibbles about the principle of equality before the law? The arrivals fast track also gives the prime minister's championing of guilt-free air travel a further cynical twist, as those who fly most are given greater inducements to take to the air, while those who fly least suffer mounting discomfort and inconvenience.

It's all part of the creeping self-segregation of the affluent minority, desperate to immunise themselves against the deficiencies of public services; in this case, the growing stress of immigration procedures.

The gated community is a global phenomenon, and nowhere more salient than in India, where the rich buy their way out of dependence on virtually all public services, including water and electricity supply. Bribing one's way to the front of the immigration queue is an extreme and particularly crass form of the same social drive. It is also, of course, illegal and officially frowned upon, whereas in the UK, the custom is effectively institutionalised, taking the form of a lawful contract between the state and a private company.

The point at issue is clearly not about cultural differences, but about the universal fact that money talks and can buy a preferential hearing even from the most developed nation states.

· Mike Marqusee writes a fortnightly column for The Hindu and is the author of Wicked Messenger: Bob Dylan and the 1960s.